1. Field of Invention
The present invention relates to Passive Infrared Radiation (PIR) motion detector and more particularly to a motion detection system with local alarm warning function and supervisory function for alarm system.
2. Description of Related Arts
A typical security alarm system consists of an alarm control panel (ACP), motion detectors, smoke detector, other security sensors, audible and voice warning devices, etc. ACP is a unit where the detection devices and wiring of the alarm are connected and managed. ACP provides power and sends operating information to the detectors and other devices. Also, ACP can integrate with wireless transmitter and receiver to communicate with the detectors and other devices. Since all appliances of the alarm system demand on the power output of the control panel, if an intruder quickly and purposely destroys the control panel to lose its power, the whole alarm system is useless no matter how intelligent the alarm system is.
U.S. Pat. Nos. 5,654,691 and 6,011,465 successfully solve the above problems by suggesting a backup device of alarm system which can monitor the conditions of the ACP such as power output, normal function, and communication. However, motion detectors in an alarm system will not work in an event of a control panel is destroyed. If an intruder waits until the audible/voice warning device goes off after the control panel is destroyed and returns back, there will be no intrusion detection and no local alarm warning. There is lack of a device which has motion detection, local alarm warning and supervisory function combined together for an enhanced alarm system with back up function